Geogrid systems are commonly used for stabilizing retain walls. In one such system, a retaining wall is formed from stacked large concrete blocks. Passages or openings are formed to extend vertically through each block. In constructing a retaining wall, a first tier of blocks is set in place. Geogrid webs are positioned to stabilize the blocks in this tier. Each web extends from behind the blocks and upwardly through a vertical opening in a block. Backfill is then placed over the web and compacted, and the web is then positioned to extend from the top of the block over the compacted backfill. After each block in the tier is secured with one or more webs and backfill is added behind the tier, a second tier of blocks may be stacked on the first tier of blocks. The blocks are then secured with geogrid webs and backfill is added behind the second tier of blocks. This process is continued until the retaining wall extends to a desired height and width. This retaining wall system is shown, for example, in U.S. Pat. No. 6,565,289 wherein two geogrid webs anchor each wall block.